Julie, Luke and Jason (aka the kid detectives) can hardly believe it. Luke's Uncle has paid their airfares to fly to London for the school holidays. Luke's Uncle's Mansion is in the London suburb of Clerkenwell. The kids read in the London Daily Mail Newspaper of a student who has gone missing from a boarding school in Clerkenwell. The kids have a surprise encounter with the missing student. Their help enables him to return to the School. Almost immediately the student, Stefan, goes missing again. Stefan's only hope now lies with the kid detectives. The kids must move fast before Stefan is taken beyond their reach. Finding where Stefan is held prisoner is only the beginning of Jason, Julie, and Luke's errand. The search will take them to the London Shipping Docks and aboard an international Merchant ship, The kids must attempt a daring midnight rescue of their new friend. A newspaper reporter joins them to give some much needed help. Will the kid detectives succeed in saving their new friend from international villians. The friends will need courage and boldness . It will not be easy.